You just get the cards at random from playing, which you don't even have to be actively doing. It doesn't let you join games that are at too high levels which is every game at this point so just wait a couple of hours for it to reset and then try joining one.

The problem with driving is that they're just going to shoehorn it into everything now. Meltdown made pretty good use of it, other than the part where you drive for three miles while getting shot by snipers from every side and then drive back because the car can't fit infinite bags inside like the DeLorean.